JPH0116776B2 - - Google Patents
Info
- Publication number
- JPH0116776B2 JPH0116776B2 JP60123900A JP12390085A JPH0116776B2 JP H0116776 B2 JPH0116776 B2 JP H0116776B2 JP 60123900 A JP60123900 A JP 60123900A JP 12390085 A JP12390085 A JP 12390085A JP H0116776 B2 JPH0116776 B2 JP H0116776B2
- Authority
- JP
- Japan
- Prior art keywords
- titanium dioxide
- suspension
- powder
- dioxide powder
- antimony
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 89
- 239000000843 powder Substances 0.000 claims description 53
- 239000004408 titanium dioxide Substances 0.000 claims description 43
- 239000000725 suspension Substances 0.000 claims description 30
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 28
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 20
- 229910001887 tin oxide Inorganic materials 0.000 claims description 16
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 claims description 16
- 229910000410 antimony oxide Inorganic materials 0.000 claims description 15
- FAPDDOBMIUGHIN-UHFFFAOYSA-K antimony trichloride Chemical compound Cl[Sb](Cl)Cl FAPDDOBMIUGHIN-UHFFFAOYSA-K 0.000 claims description 15
- VTRUBDSFZJNXHI-UHFFFAOYSA-N oxoantimony Chemical compound [Sb]=O VTRUBDSFZJNXHI-UHFFFAOYSA-N 0.000 claims description 15
- 239000011247 coating layer Substances 0.000 claims description 14
- 239000007864 aqueous solution Substances 0.000 claims description 13
- 239000002245 particle Substances 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 239000007900 aqueous suspension Substances 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 2
- 238000010304 firing Methods 0.000 claims description 2
- 238000000034 method Methods 0.000 description 26
- 238000006386 neutralization reaction Methods 0.000 description 21
- 230000000052 comparative effect Effects 0.000 description 16
- 239000000243 solution Substances 0.000 description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 238000010438 heat treatment Methods 0.000 description 6
- 239000003513 alkali Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 229910006404 SnO 2 Inorganic materials 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000000049 pigment Substances 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 230000003472 neutralizing effect Effects 0.000 description 2
- UNKOHCAZUXZPIQ-UHFFFAOYSA-N oxoantimony;hydrate Chemical compound O.[Sb]=O UNKOHCAZUXZPIQ-UHFFFAOYSA-N 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000000711 cancerogenic effect Effects 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 231100000315 carcinogenic Toxicity 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000009283 thermal hydrolysis Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000012463 white pigment Substances 0.000 description 1
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
- Conductive Materials (AREA)
Description
（産業上の利用分野）
本発明は、導電性の優れた白色粉末の製造方法
に関し、特に電子写真感光紙、静電記録紙などの
導電性付与剤として、或は、繊維、プラスチツク
スなどの帯電防止剤として有用な白色導電性粉末
の製造方法に関する。
（従来の技術）
導電性付与剤としては古くからカーボンブラツ
クが知らているが、このものは色が黒い、ビヒク
ルへの分散性が悪い、発ガン性物質を含有してい
るなど、使用に際し種々の制約を受けるのが現状
である。これに対し、最近では、二酸化チタン顔
料の表面を酸化第二スズでコーテイングしたもの
（特公昭58−39175号）、二酸化チタン顔料などの
白色導電性粉末（特開昭56−41603号、同56−
114215号、同56−114218号、同56−140028号）な
どが提案されている。
（発明が解決しようとする問題点）
前記先行特許のうち特開昭56−41603号、同56
−114215号、同56−114218号、及び同56−140028
号に提案されている被覆方法は、二酸化チタンの
加熱懸濁液中に、アルコール或は塩酸に塩化スズ
と塩化アンチモンを溶解した溶液を添加して、加
熱加水分解によりアンチモンを固溶した酸化スズ
を前記二酸化チタン粉末の表面に析出させるもの
である。この方法では、二酸化チタン懸濁液を加
熱する必要があり、またアルコール溶液を使用す
る場合は火災の危険性もあり取扱いにくく、工業
的方法としては経済的でない。特に、加熱加水分
解では、酸化スズと酸化アンチモンの沈澱析出速
度が異なるために酸化スズと酸化アンチモンを所
望の設定量、設定割合で被覆するのが困難であつ
たり、加水分解速度が遅いために、添加量のすべ
てを被覆層として形成させるには、著しく長時間
を要したり、加水分解を完結させるために高温度
に加熱する必要もあるなど種々の基本的な問題点
をかかえている。
（問題点を解決するための手段）
本発明者等は上記の問題点を解消すべく酸化ス
ズ、酸化アンチモン層の析出方法について研究し
た。その結果、二酸化チタン懸濁液に塩化スズと
塩化アンチモンの溶液を添加した後、PHをコント
ロールすることなくアルカリ水溶液を一括添加し
て中和する方法（一括添加法）では、導電性の優
れたものは得られ難いが、塩化スズ及び塩化アン
チモンの水溶液とアルカリ水溶液とを該二酸化チ
タン懸濁液に並行的に加える中和方法（並行添加
法）において、特に中和時のPHを絶えず２〜６に
保持し、かつ中和後の該懸濁液のPHもこの範囲に
維持すると以外にも導電性が著しく優れた白色粉
末が容易に得られることを見出したものである。
すなわち、本願発明は、平均粒径が0.15〜0.5μ
の二酸化チタン粉末の水性懸濁液に、塩化スズ及
び塩化アンチモンの塩酸水溶液とアルカリ水溶液
とを該懸濁液のPHを２〜６に保持するように並行
添加して該二酸化チタン粉末の表面に酸化スズと
酸化アンチモンの水和物から成る被覆層を形成さ
せ、引続き該懸濁液を該PHに維持して、被覆され
た二酸化チタン粉末を濾別、回収し、焼成するこ
とを特徴とする白色導電性粉末の製造方法であ
る。
本発明方法によつて得られる白色導電性粉末
は、二酸化チタン粉末の表面に特定量の酸化スズ
と酸化アンチモンから成る被覆層を有するもので
ある。この二酸化チタン粉末は、平均粒径が0.15
〜0.5μの顔料級の粒径に調製されたものが望まし
い。粒径がこの範囲から逸脱すると隠ぺい力が低
下し、白色顔料として機能が発揮され難くなる。
二酸化チタンは白色度に優れ、隠ぺい力も高いの
で望ましいものである。この二酸化チタンはルチ
ル型或はアナターゼ型のいずれのものも使用でき
る。
二酸化チタン粉末表面の被覆層中の酸化スズの
量は、基体の粉末に対し、SnO2として１〜30重
量％望ましくは５〜20重量％である。上記範囲よ
り少なすぎると連続した被覆層の形成が困難とな
り、導電性粉末としての機能を付与できなくな
る。また、多すぎても量の増加に応じた導電性向
上が期待できないので経済的でない。該被覆層中
の酸化アンチモンの量は、SnO2に対し、Sb2O3
として５〜30重量％望ましくは15〜25重量％であ
る。この範囲より少なすぎると所望の導電性が得
られ難くなり、また多すぎると逆に導電性が低下
したり、酸化アンチモンにより着色が強くなつた
りするので望ましくない。
本発明の白色導電性粉末の製造方法において
は、まず、基体粒子である前記二酸化チタン粉末
の水性懸濁液をつくる。懸濁液中の二酸化チタン
粉末の濃度は50〜300ｇ／望ましくは100〜200
ｇ／が適当である。懸濁液は加熱することなく
室温下に保持しても本発明方法は実施することが
できるので経済的であるが、必要に応じ例えば40
〜90度に加熱してもよい。
次に、前記二酸化チタン粉末の懸濁液に、塩化
スズ及び塩化アンチモンの塩酸水溶液とアルカリ
水溶液とを該懸濁液のPHを２〜６に保持するよう
に添加して該二酸化チタン粉末の表面に酸化スズ
と酸化アンチモンの水和物から成る被覆層を形成
させる。塩化スズ及び塩化アンチモンの塩酸水溶
液は、両塩酸水溶液を別個に添加しても或は塩化
スズと塩化アンチモンとを塩酸中に予め混合溶解
した型で添加してもよいが、予め混合した溶液を
添加するのが操作上望ましい。本発明方法におい
ては、二酸化チタン粉末の懸濁液のPHが２〜６の
酸性側に、望ましくはPH２〜４に、特に望ましく
はPH２〜３に保持されるように、塩化スズ及び塩
化アンチモンの塩酸水溶液とアルカリ水溶液とを
並行的に添加して中和することが重要である。こ
の場合、並行的に添加するとは、該塩酸水溶液と
アルカリ水溶液とを連続的に或いは断続的に添加
することも包含する。
中和時のPHが前記範囲より低くなると酸化スズ
と酸化アンチモンの水和物から成る被覆層が形成
され難くなり、また高くなると被覆層は形成され
るものの、導電性の優れた粉末が得られ難くな
る。中和するに要する時間は、該懸濁液中の二酸
化チタン粉末の濃度、塩化スズ、塩化アンチモン
の添加量などによつて異なり、一概に規定できな
いが、普通20分〜４時間、好ましくは30分〜２時
間を要し、この間ゆつくり中和するのが望まし
い。中和時間が短すぎると二酸化チタン粉末上に
均一な被覆層が形成され難くなり、長くなりすぎ
ても導電性向上に寄与しなくなり、生産性の低下
を招き工業的でない。該塩酸水溶液中の塩化スズ
の濃度は、二酸化チタンに対し酸化スズをSnO2
として１〜30重量％、望ましくは５〜20重量％の
割合で被覆するのに必要な量である。また、塩化
アンチモンの濃度は、SnO2に対し、Sn2O3とし
て５〜30重量％、望ましくは15〜25重量％の割合
で被覆するのに必要な量である。
中和剤として使用するアルカリ水溶液のアルカ
リとしては、水酸化ナトリウム、水酸化カリウ
ム、炭酸ナトリウム、炭酸カリウムなどのアルカ
リ金属の水酸化物、炭酸塩やアンモニアなどが挙
げられる。
本発明方法においては、次に中和反応終了後の
懸濁液から酸化スズ及び酸化アンチモンの水和物
で被覆された二酸化チタン粉末を濾過、洗浄して
回収するが、該粉末を回収する前の懸濁液のPHも
中和反応時のPH２〜６、望ましくはPH２〜４に維
持されていることが重要である。中和反応をPHが
２〜６に維持されるように実施しても該二酸化チ
タン回収前の懸濁液の最終PHがこの範囲から逸脱
した場合は、所望の導電性を持つ二酸化チタン粉
末が得られ難い。
回収した二酸化チタン粉末はその後必要に応じ
て乾燥した後400〜1200℃、望ましくは500〜700
℃の温度で焼成して酸化スズ及び酸化アンチモン
の水和物を酸化スズ及び酸化アンチモンの被覆層
とした後、通常の粉砕処理を施して白色導電性粉
末とする。焼成時間は30分〜５時間望ましくは１
〜２時間が適当である。焼成温度が上記範囲より
逸脱すると所望の導電性が得られ難くなる。
以上の通り、本発明方法は、アルコールなどの
有機溶媒を使用しないので、火災などの危険性が
なく、工業的に優れた方法であり、かつ、従来の
熱加水分解法とは異なり、酸化スズ及び酸化アン
チモンの析出速度、析出量などを自由にコントロ
ールでき、更に酸化スズ、酸化アンチモンの均一
な被覆層が得られるものである。
以下に、本発明方法を実施例で説明する。
実施例 １
平均粒径0.25μのルチル型二酸化チタン粉末を
水に分散させて濃度100ｇ／の懸濁液とした。
この懸濁液を70℃に加熱した後この中に、塩化ス
ズ（SnCl4・5H2O）34.9ｇ及び酸化アンチモン
（SbCl3）3.8ｇを2N−塩酸溶液500c.c.に溶解した
溶液と10％の水酸化ナトリウム水溶液とを該懸濁
液のPHを２〜３に維持するように60分間にわたつ
て並行添加して、二酸化チタン粉末上に酸化スズ
及び酸化アンチモンの水和物から成る被覆層を形
成させた。なお、このときの懸濁液の最終PHは
2.9であつた。次に、被覆された二酸化チタン粉
末を濾過し、濾液の比抵抗が50μSになるまで洗
浄して被覆された二酸化チタン粉末を回収した。
回収された二酸化チタン粉末を電気炉で600℃
にて２時間焼成し、次いでパルペライザーで粉砕
して白色導電性粉末を得た。
実施例 ２
実施例１において、中和時のPHを４〜５に保持
するように中和したこと以外は同様に処理した。
なお、本実施例では中和終了後のPHは5.0になつ
たので、塩酸を加えて最終的にPHを3.0に調整し
た。
実施例 ３
実施例１において、二酸化チタン粉末の懸濁液
を加熱することなく室温（25℃）のものを使用し
たこと以外は同様に処理した。なお、中和終了後
の最終PHは2.5であつた。
実施例 ４
実施例３において、中和時のPHを４〜５に保持
するように中和したこと以外は同様に処理した。
なお、中和終了後のPHは4.0になつたので、塩酸
を加えて最終的にPHを3.0に調整した。
比較例 １
実施例１において、中和時のPHを６〜９に保持
するように中和したこと及び最終PHを7.0に調整
したこと以外は同様に処理した。
比較例 ２
実施例３において、中和時のPHを６〜９に保持
するように中和したこと及び最終PHを3.0に調整
したこと以外は同様に処理した。
比較例 ３
実施例３において、中和時のPHを６〜９に保持
するように中和したこと及び最終PHを7.0に調整
したこと以外は同様に処理した。
比較例 ４
実施例３において、最終PHを7.0に調整したこ
と以外は同様に処理した。
比較例 ５
実施例４において、最終PHを7.0に調整したこ
と以外は同様に処理した。
比較例 ６
実施例１と同じ二酸化チタン粉末を100ｇ／
の懸濁液とし、これを70℃に加熱した後、この中
に、塩化スズ（SnCl4・5H2O）34.9ｇ及び塩化ア
ンチモン（SbCl3）3.8ｇを2N−塩酸溶液500c.c.に
溶解した溶液を30分間にわたつて添加した。その
後撹拌しながら10％の水酸化ナトリウム水溶液を
40分間にわたつて添加し、懸濁液のPHを7.0に調
整した後実施例１と同様にして濾過、洗浄した後
電気炉で600℃にて２時間焼成し、パルペライザ
ーで粉砕した。
比較例 ７
比較例６において、二酸化チタン粉末の懸濁液
を加熱することなく室温（25℃）のものを使用し
たことを以外は同様に処理した。
比較例 ８
比較例６において、二酸化チタン粉末の懸濁液
を加熱することなく室温（25℃）のものを使用し
たこと及び中和終了時のPHを3.0に調整すること
以外は同様に処理した。
試験例 １
前記実施例及び比較例で得られた二酸化チタン
粉末についてその粉体抵抗（Ωcm）を次の方法で
測定し、表１の結果を得た。
（粉体抵抗の評価）
試料粉末を100Kg／cm2の圧力で成型して円柱状
圧粉末（直径18mm、厚さ３mm）とし、その直流抵
抗を測定した。
(Industrial Application Field) The present invention relates to a method for producing a white powder with excellent conductivity, and in particular as a conductivity imparting agent for electrophotographic paper, electrostatic recording paper, etc., or for use in fibers, plastics, etc. The present invention relates to a method for producing a white conductive powder useful as an antistatic agent. (Prior art) Carbon black has been known as a conductivity imparting agent for a long time, but it has various problems when used, such as being black in color, having poor dispersibility in vehicles, and containing carcinogenic substances. The current situation is that it is subject to the following restrictions. In contrast, recently, titanium dioxide pigments coated on the surface with stannic oxide (Japanese Patent Publication No. 58-39175), white conductive powders such as titanium dioxide pigments (Japanese Patent Publications No. 56-41603, 56 −
114215, No. 56-114218, No. 56-140028), etc. have been proposed. (Problems to be solved by the invention) Among the preceding patents, JP-A-56-41603 and JP-A-56
−114215, No. 56-114218, and No. 56-140028
The coating method proposed in the issue involves adding a solution of tin chloride and antimony chloride dissolved in alcohol or hydrochloric acid to a heated suspension of titanium dioxide, and then heating and hydrolyzing it to form a tin oxide solution with antimony dissolved therein. is deposited on the surface of the titanium dioxide powder. In this method, it is necessary to heat the titanium dioxide suspension, and if an alcohol solution is used, there is a risk of fire and it is difficult to handle, so it is not economical as an industrial method. In particular, in thermal hydrolysis, it is difficult to coat tin oxide and antimony oxide in the desired amount and ratio because the precipitation rates of tin oxide and antimony oxide are different, and because the hydrolysis rate is slow, However, there are various basic problems such as it takes a very long time to form a coating layer using the entire amount added, and heating to a high temperature is necessary to complete the hydrolysis. (Means for Solving the Problems) In order to solve the above-mentioned problems, the present inventors have studied methods for depositing tin oxide and antimony oxide layers. As a result, the method of adding a solution of tin chloride and antimony chloride to a titanium dioxide suspension and then neutralizing it by adding an alkaline aqueous solution all at once without controlling the pH (bulk addition method) has been found to have excellent conductivity. Although this is difficult to obtain, in the neutralization method (parallel addition method) in which an aqueous solution of tin chloride and antimony chloride and an aqueous alkali solution are added to the titanium dioxide suspension in parallel, the pH during neutralization is constantly adjusted to between 2 and 2. It has been discovered that by maintaining the pH of the suspension at 6 and also maintaining the pH of the suspension after neutralization within this range, a white powder with extremely excellent conductivity can be easily obtained. That is, the present invention has an average particle size of 0.15 to 0.5μ.
To an aqueous suspension of titanium dioxide powder, a hydrochloric acid aqueous solution of tin chloride and antimony chloride and an alkali aqueous solution are added in parallel so as to maintain the pH of the suspension at 2 to 6, and the surface of the titanium dioxide powder is A coating layer consisting of a hydrate of tin oxide and antimony oxide is formed, the suspension is maintained at the pH, and the coated titanium dioxide powder is filtered, collected, and fired. This is a method for producing white conductive powder. The white conductive powder obtained by the method of the present invention has a coating layer on the surface of the titanium dioxide powder containing a specific amount of tin oxide and antimony oxide. This titanium dioxide powder has an average particle size of 0.15
Preferably, the particles are prepared to a pigment-grade particle size of ~0.5μ. If the particle size deviates from this range, the hiding power will decrease and it will be difficult for the pigment to function as a white pigment.
Titanium dioxide is desirable because it has excellent whiteness and high hiding power. This titanium dioxide can be either rutile type or anatase type. The amount of tin oxide in the coating layer on the surface of the titanium dioxide powder is 1 to 30% by weight as SnO2 , preferably 5 to 20% by weight, based on the base powder. If the amount is too small than the above range, it will be difficult to form a continuous coating layer and it will not be possible to provide the function as a conductive powder. Furthermore, if the amount is too large, it is not economical because the conductivity cannot be expected to improve in proportion to the increase in the amount. The amount of antimony oxide in the coating layer is Sb 2 O 3 with respect to SnO 2
The amount is preferably 5 to 30% by weight, preferably 15 to 25% by weight. If the amount is less than this range, it will be difficult to obtain the desired conductivity, and if it is too much, the conductivity will decrease or the coloring will become stronger due to antimony oxide, which is not desirable. In the method for producing white conductive powder of the present invention, first, an aqueous suspension of the titanium dioxide powder, which is the base particle, is prepared. The concentration of titanium dioxide powder in the suspension is 50-300g/preferably 100-200g.
g/ is appropriate. The method of the present invention can be carried out even if the suspension is kept at room temperature without heating, so it is economical.
May be heated to ~90 degrees. Next, a hydrochloric acid aqueous solution and an alkali aqueous solution of tin chloride and antimony chloride are added to the suspension of the titanium dioxide powder so as to maintain the pH of the suspension at 2 to 6, so that the surface of the titanium dioxide powder is to form a coating layer consisting of a hydrate of tin oxide and antimony oxide. The hydrochloric acid aqueous solution of tin chloride and antimony chloride may be added either by adding both hydrochloric acid aqueous solutions separately or by adding the tin chloride and antimony chloride in a premixed and dissolved form in hydrochloric acid. It is operationally desirable to add In the method of the present invention, tin chloride and antimony chloride are added so that the pH of the suspension of titanium dioxide powder is maintained on the acidic side of 2 to 6, preferably 2 to 4, particularly preferably 2 to 3. It is important to neutralize by adding an aqueous hydrochloric acid solution and an aqueous alkaline solution in parallel. In this case, adding in parallel also includes adding the hydrochloric acid aqueous solution and the alkaline aqueous solution continuously or intermittently. If the pH at the time of neutralization is lower than the above range, it will be difficult to form a coating layer consisting of hydrated tin oxide and antimony oxide, and if it is higher, a coating layer will be formed, but a powder with excellent conductivity will not be obtained. It becomes difficult. The time required for neutralization varies depending on the concentration of titanium dioxide powder in the suspension, the amount of tin chloride, antimony chloride, etc., and cannot be absolutely specified, but it is usually 20 minutes to 4 hours, preferably 30 minutes. It takes minutes to 2 hours, and it is desirable to neutralize slowly during this time. If the neutralization time is too short, it will be difficult to form a uniform coating layer on the titanium dioxide powder, and if the neutralization time is too long, it will not contribute to improving conductivity, leading to a decrease in productivity and not being industrially practical. The concentration of tin chloride in the hydrochloric acid aqueous solution is as follows: titanium dioxide, tin oxide, SnO 2
The amount necessary for coating is 1 to 30% by weight, preferably 5 to 20% by weight. Further, the concentration of antimony chloride is an amount necessary to coat SnO 2 at a ratio of 5 to 30% by weight, preferably 15 to 25% by weight as Sn 2 O 3 . Examples of the alkali in the aqueous alkali solution used as a neutralizing agent include alkali metal hydroxides, carbonates, and ammonia such as sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate. In the method of the present invention, titanium dioxide powder coated with tin oxide and antimony oxide hydrate is then collected from the suspension after the neutralization reaction by filtration and washing, but before the powder is collected, It is also important that the pH of the suspension is maintained at PH2 to 6, preferably PH2 to 4, during the neutralization reaction. Even if the neutralization reaction is carried out to maintain the pH between 2 and 6, if the final pH of the suspension before titanium dioxide recovery deviates from this range, titanium dioxide powder with the desired conductivity may be Hard to obtain. The recovered titanium dioxide powder is then dried as necessary and heated to 400-1200℃, preferably 500-700℃.
The hydrate of tin oxide and antimony oxide is fired at a temperature of 0.degree. C. to form a coating layer of tin oxide and antimony oxide, and then subjected to a conventional pulverization treatment to obtain a white conductive powder. Baking time is preferably 30 minutes to 5 hours.
~2 hours is appropriate. If the firing temperature deviates from the above range, it becomes difficult to obtain the desired conductivity. As described above, the method of the present invention does not use organic solvents such as alcohol, so there is no risk of fire, and it is an industrially superior method. The precipitation rate and amount of antimony oxide can be controlled freely, and a uniform coating layer of tin oxide and antimony oxide can be obtained. The method of the present invention will be explained below using examples. Example 1 Rutile titanium dioxide powder with an average particle size of 0.25 μm was dispersed in water to form a suspension with a concentration of 100 g/ml.
After heating this suspension to 70°C, a solution of 34.9 g of tin chloride (SnCl 4 .5H 2 O) and 3.8 g of antimony oxide (SbCl 3 ) dissolved in 500 c.c. of 2N hydrochloric acid solution was added. A 10% aqueous sodium hydroxide solution was added in parallel over a period of 60 minutes to maintain the pH of the suspension between 2 and 3 to form a mixture of tin oxide and antimony oxide hydrates on the titanium dioxide powder. A coating layer was formed. In addition, the final pH of the suspension at this time is
It was 2.9. Next, the coated titanium dioxide powder was filtered and washed until the specific resistance of the filtrate became 50 μS to recover the coated titanium dioxide powder. The recovered titanium dioxide powder is heated to 600℃ in an electric furnace.
The mixture was fired for 2 hours, and then pulverized using a pulperizer to obtain a white conductive powder. Example 2 The same procedure as in Example 1 was carried out except that the pH at the time of neutralization was maintained at 4 to 5.
In this example, the pH after neutralization was 5.0, so hydrochloric acid was added to finally adjust the pH to 3.0. Example 3 The same procedure as in Example 1 was carried out except that the suspension of titanium dioxide powder was used at room temperature (25° C.) without being heated. The final pH after neutralization was 2.5. Example 4 The same procedure as in Example 3 was carried out except that the pH at the time of neutralization was maintained at 4 to 5.
The pH after neutralization was 4.0, so the pH was finally adjusted to 3.0 by adding hydrochloric acid. Comparative Example 1 The same procedure as in Example 1 was carried out except that the pH at the time of neutralization was maintained at 6 to 9 and the final pH was adjusted to 7.0. Comparative Example 2 The same procedure as in Example 3 was carried out except that the pH at the time of neutralization was maintained at 6 to 9 and the final pH was adjusted to 3.0. Comparative Example 3 The same procedure as in Example 3 was carried out except that the pH at the time of neutralization was maintained at 6 to 9 and the final pH was adjusted to 7.0. Comparative Example 4 The same procedure as in Example 3 was carried out except that the final pH was adjusted to 7.0. Comparative Example 5 The same procedure as in Example 4 was carried out except that the final pH was adjusted to 7.0. Comparative Example 6 100g of the same titanium dioxide powder as in Example 1
After heating this to 70°C, 34.9 g of tin chloride (SnCl 4.5H 2 O) and 3.8 g of antimony chloride (SbCl 3 ) were added to 500 c.c. of a 2N hydrochloric acid solution. The dissolved solution was added over 30 minutes. Then add 10% aqueous sodium hydroxide solution while stirring.
The mixture was added over 40 minutes, and the pH of the suspension was adjusted to 7.0. The suspension was then filtered and washed in the same manner as in Example 1, then calcined in an electric furnace at 600°C for 2 hours, and pulverized with a pulperizer. Comparative Example 7 The same procedure as in Comparative Example 6 was carried out except that the titanium dioxide powder suspension was used at room temperature (25° C.) without being heated. Comparative Example 8 The same procedure as in Comparative Example 6 was carried out except that the suspension of titanium dioxide powder was used at room temperature (25°C) without heating and the pH at the end of neutralization was adjusted to 3.0. . Test Example 1 The powder resistance (Ωcm) of the titanium dioxide powders obtained in the Examples and Comparative Examples was measured by the following method, and the results shown in Table 1 were obtained. (Evaluation of Powder Resistance) The sample powder was molded at a pressure of 100 kg/cm 2 to form a cylindrical compact (diameter 18 mm, thickness 3 mm), and its DC resistance was measured.
【表】
実施例 ５
前記実施例において、二酸化チタン粉末の懸濁
液に添加する塩化スズ（SnCl4・5H2O）及び塩
化アンチモン（SbCl3）の量を各々23.3ｇ及び5.0
ｇに変更する以外は同様に処理した。なお、中和
終了後のPHは2.8であつた。
比較例 ９
前記比較例６において、二酸化チタン粉末の懸
濁液に添加する塩化スズ（SnCl4・5H2O）及び
塩化アンチモン（SbCl3）の量を各々23.3ｇ及び
5.0ｇに変更する以外は同様に処理した。
比較例 10
前記比較例６において、二酸化チタン粉末の懸
濁液に添加する塩化スズ（SnCl4・5H2O）及び
塩化アンチモン（SbCl3）の量を各々23.3ｇ及び
5.0ｇに変更すること及び中和終了時のPHを3.0に
調整すること以外は同様に処理した。
試験例 ２
前記実施例５及び比較例９及び10で得られた二
酸化チタン粉末について試験例１と同様の方法で
粉体抵抗を測定し、表２の結果を得た。[Table] Example 5 In the above example, the amounts of tin chloride (SnCl 4 .5H 2 O) and antimony chloride (SbCl 3 ) added to the suspension of titanium dioxide powder were 23.3 g and 5.0 g, respectively.
The same process was carried out except that the temperature was changed to g. The pH after neutralization was 2.8. Comparative Example 9 In Comparative Example 6, the amounts of tin chloride (SnCl 4 5H 2 O) and antimony chloride (SbCl 3 ) added to the suspension of titanium dioxide powder were 23.3 g and 23.3 g, respectively.
The same treatment was carried out except that the amount was changed to 5.0 g. Comparative Example 10 In Comparative Example 6, the amounts of tin chloride (SnCl 4 .5H 2 O) and antimony chloride (SbCl 3 ) added to the suspension of titanium dioxide powder were 23.3 g and 23.3 g, respectively.
The same treatment was carried out except that the amount was changed to 5.0 g and the pH at the end of neutralization was adjusted to 3.0. Test Example 2 The powder resistance of the titanium dioxide powders obtained in Example 5 and Comparative Examples 9 and 10 was measured in the same manner as in Test Example 1, and the results shown in Table 2 were obtained.
【表】
（発明の効果）
表１及び表２の結果から明らかなように、本発
明方法によつて得られる白色導電性粉末は、優れ
た導電性を示す。[Table] (Effects of the Invention) As is clear from the results in Tables 1 and 2, the white conductive powder obtained by the method of the present invention exhibits excellent conductivity.
Claims (1)
水性懸濁液に、塩化スズ及び塩化アンチモンの塩
酸水溶液とアルカリ水溶液とを該懸濁液のPHを２
〜６に保持するように並行添加して該二酸化チタ
ン粉末の表面に酸化スズと酸化アンチモンの水和
物から成る被覆層を形成させ、引続き該懸濁液を
該PHに維持して、被覆された二酸化チタン粉末を
濾別、回収し、焼成することを特徴とする白色導
電性粉末の製造方法。1. To an aqueous suspension of titanium dioxide powder with an average particle size of 0.15 to 0.5μ, add a hydrochloric acid aqueous solution and an alkaline aqueous solution of tin chloride and antimony chloride to bring the pH of the suspension to 2.
A coating layer consisting of a hydrate of tin oxide and antimony oxide is formed on the surface of the titanium dioxide powder by parallel addition so that the pH is maintained at 6. 1. A method for producing white conductive powder, which comprises filtering, collecting, and firing titanium dioxide powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12390085A JPS61286221A (en) | 1985-06-07 | 1985-06-07 | Preparation of white electroconductive powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12390085A JPS61286221A (en) | 1985-06-07 | 1985-06-07 | Preparation of white electroconductive powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61286221A JPS61286221A (en) | 1986-12-16 |
| JPH0116776B2 true JPH0116776B2 (en) | 1989-03-27 |
Family
ID=14872117
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12390085A Granted JPS61286221A (en) | 1985-06-07 | 1985-06-07 | Preparation of white electroconductive powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61286221A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01264932A (en) * | 1988-04-15 | 1989-10-23 | Ishihara Sangyo Kaisha Ltd | Acicular titanium dioxide having characteristic required for pigment and its production |
| DE3929057A1 (en) * | 1989-09-01 | 1991-03-07 | Metallgesellschaft Ag | ELECTRICALLY CONDUCTIVE RUTILE MIXED-PHASE PIGMENT, METHOD FOR THE PRODUCTION THEREOF AND THE USE THEREOF |
| JP3557688B2 (en) * | 1995-02-09 | 2004-08-25 | 株式会社クボタ | Strip-shaped conductive powder, its production method and use |
| JP5552371B2 (en) * | 2010-05-31 | 2014-07-16 | 三菱マテリアル株式会社 | White conductive powder and method for producing the same |
| WO2023136283A1 (en) * | 2022-01-13 | 2023-07-20 | 石原産業株式会社 | Coated aluminum oxide particles, method for manufacturing same, and use thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58209002A (en) * | 1982-05-28 | 1983-12-05 | チタン工業株式会社 | Method of producing white conductive powder |
| JPS59102820A (en) * | 1982-12-02 | 1984-06-14 | Res Inst For Prod Dev | Production of electrically-conductive alkali metal titanate |
-
1985
- 1985-06-07 JP JP12390085A patent/JPS61286221A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58209002A (en) * | 1982-05-28 | 1983-12-05 | チタン工業株式会社 | Method of producing white conductive powder |
| JPS59102820A (en) * | 1982-12-02 | 1984-06-14 | Res Inst For Prod Dev | Production of electrically-conductive alkali metal titanate |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61286221A (en) | 1986-12-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR950011338B1 (en) | Acicular electro conductive titanium oxide and process for production same | |
| JP2598282B2 (en) | Method for producing rutile-adhered mica pigment | |
| KR0136789B1 (en) | Electrically conductive pigment platelets | |
| JP3357107B2 (en) | White conductive titanium dioxide powder and method for producing the same | |
| JP5629344B2 (en) | Tin oxide particles and method for producing the same | |
| JP2000026755A (en) | Electroconductive pigment | |
| JPH0912919A (en) | Golden pigment | |
| JPH08109341A (en) | Conductive pigment | |
| US5322561A (en) | Conductive flaky pigments | |
| JPS63233016A (en) | Acicular electrically conductive titanium oxide and its production | |
| JPH0116776B2 (en) | ||
| JPH0782508A (en) | Stabilized conductive pigment | |
| JP3422832B2 (en) | Dendritic or starfish-shaped fine titanium dioxide and method for producing the same | |
| JPH07138021A (en) | Dendritic or stelliform titanium dioxide fine particle and its production | |
| JPS6320342A (en) | Production of electroconductive mica microparticle | |
| JP3609159B2 (en) | Acicular conductive antimony-containing tin oxide fine powder and method for producing the same | |
| JP2844011B2 (en) | Conductive fine powder and method for producing the same | |
| JPS621574B2 (en) | ||
| JP4078660B2 (en) | Conductive titanium oxide, process for producing the same, and plastic composition containing the same | |
| DE4237355A1 (en) | Electroconductive pigment with shell of fluoride-doped tin oxide - and use in antistatic lacquer, plastics and fibre which is non-toxic and has good properties in use | |
| JP3647929B2 (en) | Method for producing conductive antimony-containing tin oxide fine powder | |
| JPH0114174B2 (en) | ||
| JP2858271B2 (en) | Method for producing conductive fine powder | |
| JPH1111947A (en) | Production of antimony doped tin oxide powder and coating material containing the same | |
| JPH0292824A (en) | Acicular low oxidized titanium and production thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| EXPY | Cancellation because of completion of term |